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An Epic Journey for Courageous Fish Steelhead at Selway Falls
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Description: This is a 3 day lesson and activity including: Day 1: Salmon biology and research Day 2: “Following Fishes” guided internet activity Day 3: Class discussion Juvenile Steelhead Parr Camas Creek, Idaho
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Day 1: Salmon biology and research 1. General salmon vocabulary 2. Basic salmon life history 3. Idaho salmon descriptions 4. Dangers to migrating salmon 5. Salmon research methods and an overview of research technology Rainbow/Steelhead Trout
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Vocabulary 1: Movement Anadromous: fish born in fresh water streams migrate to the ocean as juveniles. They mature in the ocean and return to their home streams to reproduce. Migration: movement from one place to another Emigration: movement out of an area Immigration: movement into an area Salmon River
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Vocabulary 2: Reproduction Redd: the gravel nest created by a female salmon with her tail. Spawn: the mating behavior of salmon in which the female builds a redd in the gravel stream bottom. She then lays eggs that the male fertilizes by releasing sperm. The redd is covered with small gravel. Female Chinook building a redd Redd: eggs in gravel
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Vocabulary 3: Life Stages Alevin: newly hatched fish that stays in the redd as it develops further while feeding off of a yolk sack. Fry: a juvenile salmon that has emerged from the redd. Parr: juvenile salmon feeding and growing in freshwater. These have dark bars 0r spots on their sides. Smolt: a juvenile salmon emigrating downstream toward the ocean. This loses its spots and takes on a silvery hue. Alevins emerging as fry
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To Stay or Go: a life history decision Salmon species divide into two distinct populations: Some fry remain in the stream and become residents. Some fry turn into smolts and emigrate. The decision to smolt is influenced by the growth rate of the fish and it’s genetic makeup. Resident and anadromous populations of the same species can inter-mate. Spawning Kokanee: Can you spot the resident trout?
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The Run: return of adult fish Fish of the same species return to spawn at the same time Most salmon die after spawning. Kokanee run bunched up at a weir.
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Oncorhynchus mykiss: Resident: Rainbow Trout Anadromous: Steelhead Trout Spend 1 to 6 years in freshwater before emigrating. Spend 1 to 3 years in the ocean. After spawning, some can return to the ocean and then spawn a second time. Wild Juvenile Steelhead Hatchery Adult Steelhead
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Oncorhynchus tshawytscha: Resident: none Anadromous: Chinook (King) Salmon Spend 0 to 2 years in freshwater before emigrating. Spend 0 to 4 years in the ocean. Jack: an adult male that goes to the ocean and returns to it’s home stream within a single year. Jills (female) are not common. Wild Adult Chinook Wild Juvenile Chinook
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It is often difficult to tell Chinook and Steelhead juveniles apart. Juvenile Fish: Steelhead (rainbow) trout Chinook salmon
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Oncorhynchus nerka: Resident: Kokanee Anadromous: Sockeye Salmon Spend 1 to 2 years in fresh water streams before emigrating. Spend 1 to 3 years in the ocean. Male Female As fry turn into smolts they lose their spots. Kokanee
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Hatchery vs. Wild Fish: Since Idaho’s salmon are listed as threatened under the Endangered Species Act, we balance harvest and dam impacts by producing fish in hatcheries. To mark a fish as “hatchery” instead of wild the adipose fin is removed. Only hatchery fish can be harvested. If a wild fish is caught it must be released (except in some tribal fisheries). Clearwater Hatchery
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Predators: eagle, hawk, osprey, bear, raccoon, muskrat, otter, bigger fish, seals, pelicans, people Starvation: fish eat insects who's populations can vary depending depending on habitat quality Pollution: herbicides, pesticides, agricultural and industrial runoff, Low water flow: intermittent streams dry out or water is diverted and fish are stranded Increased water temp: higher temperatures decrease oxygen content and lead to suffocation Erosion: fine soil particles bury redds and suffocate eggs and hatchling fish Dangers to Juvenile Salmon: Steelhead juvenile eating smaller fish Pelican eating trout
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Dangers Posed by Dams: Fish get lost in large reservoirs and do not complete their migration down to the ocean or back to natal streams. Fish are killed in turbines. Screens keep most fish from entering the turbine area and funnel them into fish passage tunnels. Some fish still get caught in turbine blades. The dam creates a bottleneck where large predators wait for fish. Animals like otters, seals, pikeminnows, and raptors know fish have limited travel options and position themselves where they can easily eat passing fish. Bald Eagle on the Dalles Dam
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Dam Construction: Basic dam characteristics: Turbine (2) powered by water flow (1) Generator (3) to convert kinetic energy of water flow into electricity Energy transfer system (4) The Powerhouse with generators. Each generator is powered by a fan shaped turbine (below). 1,200-ton rotor
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Lower Granite Dam Crossing the Dams: A dam is a solid structure and some dams completely prevent fish movement. Others have pathways for fish migration. Spillway: water over the top of the dam Juvenile bypass: tunnel built through the dam to facilitate juvenile fish movement Turbine: water passing under the dam turns fan shaped blades to create electricity Fish ladder: returning adults climb up and over every dam Barge: juvenile fish are collected from reservoirs and transported down stream in large tank boats Lock: allows boats to move from one side of the dam to the other Lock Spillway Powerhouse Juvenile Fish Barge Fish Ladder
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Fish survival: a Chinook example For the last 10 years: There are about 970 million juvenile Chinook born in Idaho streams each year. (969,840,000 ) Of those juveniles only 0.2% survive to become smolts. ( 1,500,000 ) 1.7% of fish that survive to smolt return as adults. (25,839) Of all the fish that are born less than 1% return to spawn. (0.003%) Why do they choose to migrate? Our small cold streams don’t provide enough resources to sustain large populations. It is better for the fish to migrate to the ocean and feed there. Then they come back to their natal streams to spawn because the eggs needs cold, shallow, gravel beds. FINAL 2012 CSS Annual Report
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Picket Weir Fish Research: In order to study fish…we have to catch them first: Screw Trap: funnels juvenile fish into a holding tank Weir: blocks a stream so adult fish can be trapped and sampled before passing Snorkeling Survey: fish are observed and counted Since salmon are listed as threatened under the Endangered Species Act, sampling techniques must be non lethal and fish must be returned to their streams. Snorkeling Crew Screw Trap
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Sampling Techniques: When a fish is caught for sampling, several techniques are used: Fin clip: part of a fin tissue is removed for genetic analysis Scale sample: a few scales are scraped off and used to determine fish age Fish Characteristics: sex, length, weight, and condition are recorded Tagging: various tags are used to track fish Adult Scale Saltwater growth Freshwater Growth
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Fish Tagging: PIT tag: placed inside a fish’s abdomen, “PIT” = passive integrated transponder has a unique number that is recorded in the PTAGIS database Each pit tag has a unique code that can be read by an interrogator like those placed in an array or on dams PIT Array: a wire in a stream or dam that detects the passage of a fish with a PIT tag and records it in the Ptagis database PTAGIS database: a public database that records the movement of fish and their individual characteristics ( PTAGIS = pit tag information system) Columbia River DART database: daily data plus historic information dating back to 1878 focusing on the Columbia Basin dams and fish passage (DART=data access in real time) Pit tags
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Technology and Fish Management: A simplified and general overview: 1. Place a screw trap in the steam. 2. Count, measure, and pit tag all juvenile fish captured (C). 3. Release a known number of tagged fish upstream above the screw trap (M). 4. Count recaptured fish (you know by the PIT tag) (R). 5. Estimate total juvenile fish population: N = C/(R/M). 6. Use PIT Array to track fish movement and survival as fish emigrate and again as they immigrate. All this data is saved in the PTAGIS database. 7. Use PIT tag detection combined with dam fish passage window counters and population structure to estimate fish return population. This is found in the DART database. 8. Use return estimates to set harvest limits. How big are you?
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Traveling on the Pit Array: When a fish is tagged, it’s species, measurements, location, and the tag number, are all recorded in the Ptagis database. Each time a tagged fish crosses an array it’s location and the date are recorded. Using the PIT tag number all available data can be retrieved from the database Screen shot from PTAGIS Map of Pit Arrays
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Day 2: Following Fishes For the next section we will be working on computers. Each of you will be assigned 1 real pit tag number. You will use the PTAGIS and DART databases to answer a series of questions. Then we will use this data to plot fish movement on a large map and discuss the survival of migrating fish.
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Day 3: Mapping Fish Movement Today we will combine all of our data and plot this on a map We will then discuss our results. Map of Pit Arrays (this is from the PTAGIS web site)
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The Snake River Basin:
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Guiding questions: 1. What did we learn from this exercise? 1. Dams? 2. Fish migration? 3. Geography? 4. Technology? 5. Careers? 2. What impacts have humans had on migrating salmon? 3. What impacts have salmon had on humans? 4. What do you think is going to happen in the future? 1. Why? Want more? Check out the newest F.I.S.H. at the Idaho Department of Fish and Game’s web site ! http://207.109.38.126/idaho/web/apps/index_main.php
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Resources and Sources: American Fisheries Society: http://fisheries.org/ Columbia Basin Research DART: http://www.cbr.washington.edu/dart Federal Caucus of Salmon Recovery: http://www.salmonrecovery.gov/Home.aspx Fish Passage Center: http://fpc.org/about_fpc.html FINAL 2012 CSS Annual Report - 11/30/12 FINAL 2012 CSS Annual Report Idaho Department of Fish and Game: http://fishandgame.idaho.gov/public/fish/ IDFG Report Number 12-18 October 2012 Idaho Power: http://www.idahopower.com/OurEnvironment/FishAquatic/Chinook/default.cfm Pacific States Marine Fisheries Commission: http://www.psmfc.org/ Ptagis.org : http://www.ptagis.org/home Schoolgen (Genesis Energy): http://www.schoolgen.co.nz/a/a_assets_hydro.aspx US Army Corps of Engineers: Walla Walla District http://www.nww.usace.army.mil/Missions/FishPrograms.aspx Washington Department of Fish and Wildlife: http://wdfw.wa.gov/fishing/washington/fishing101/
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